PIK3CA and malignant colon neoplasm: To understand the importance of PI3K signaling in KRAS mutated colon cancer, we selected human colon cell lines based on mutation status of KRAS and PI3K genes (Table 1) Cell proliferation was measured using the CCK‐8 assay after a 48 h incubation with BKM120, cetuximab, or a combination of both.